1. The Field of the Invention
The present invention generally relates to hazard detection. More specifically, the present invention relates to hazard detection units that provide pre-alarms for developing hazardous conditions.
2. The Relevant Technology
Hazard detectors use a variety of sensors to detect substances in the air that are harmful or indicate the development of a hazardous situation. For example, carbon monoxide (CO) and radon gas are substances that can be harmful to humans and animals if exposed to high amounts. However, these substances are difficult to detect with the human senses because they are colorless, odorless, and tasteless. A hazard detector can detect the presence of these substances and prevent the harmful effects of exposure by alarming a user. In other instances, a substance such as smoke, while not necessarily harmful in and of itself, can indicate the development of a hazardous situation, such as fire.
Hazard detectors are certified under standards defined by a governing body, such as the Occupational Safety and Health Administration (OSHA), or companies that perform safety testing, such as Underwriters Laboratories (UL). For example, UL defines thresholds for when smoke detectors and CO detectors should sound an alarm. UL also defines the characteristics of the alarm, such as the volume, pitch, and pattern of the sound.